This invention relates to a V-belt drive in which a pulley for the drive is designed so as to cause air generated by rotation of the pulley itself to operate to cool the V-belt as it leaves and enters the pulley. More specifically, the present invention relates to an improvement on a variable speed pulley of a centrifugal clutch type which is shown and described in a co-pending patent application, Ser. No. 122,594, filed Feb. 19, 1980 by Keni K. Prasad and now U.S. Pat. No. 4,313,728.
It is heretofore been known to provide annular flanges on the outer side of a variable speed pulley and to provide openings in that pulley so that air trapped inside the flange may move outwardly by mechanism which is internally of the flange. Such an arrangement is shown in U.S. Pat. No. 3,962,927, which issued to Guy Beaudoin and Marcel Vincent on June 15, 1976. Generally, such openings or air passages in the flange served only the purpose of having an opening through which air can exit. In the specific patent referred to, the device was used in the environment of a snowmobile and adjacent the engine of the snowmobile and consequently, the air exiting through these openings served the purpose of cooling the compartment in which the engine was mounted.
The life of a V-belt is generally inversely proportional to the temperature of the belt itself when it is in operation. A belt that generates a lot of heat and raises the internal temperature of the belt will normally have a considerable lower life expectancy than a belt which is kept at a comparatively low temperature. The temperature of a belt moving on a pulley of the type shown in the aforementioned U.S. Patent is not affected considerably due to the slightly lower temperature in the compartment. However, if a stream of air is moved directly against the belt, the temperature of the belt does drop considerably.